(1) The wall thickness coverage of seamless steel pipes is relatively wide and can achieve small diameters and large wall thicknesses and large diameters and large wall thicknesses, but the length is generally limited (only a few manufacturers can produce ultra-long pipes); stainless steel welded pipes The wall thickness can be relatively thin, and the wall thickness of large diameter and small diameter can be achieved. Theoretically, the length of the long roll is as long as the welded pipe can be produced. Generally speaking, the thicker the pipe, the better to choose seamless pipe, the thinner the pipe, the better to choose welded pipe.
(2) In terms of wall thickness uniformity and concentricity, stainless steel welded pipes are better than stainless steel seamless pipes. Because the thickness tolerance of cold-rolled plates is relatively uniform, the deformation during the forming process is even. However, the weld seam protrudes, and different companies and standards have different welding height requirements. Under special circumstances, you can weld first and then cold draw or cold roll; the seamless pipe rolling process is affected by equipment accuracy, material performance, and other factors, and there is a thickness difference. There are problems with unevenness and concentricity, but the roundness is better than that of welded pipes.
(3) Function, stainless steel welded pipe has better uniformity and better surface quality. The tube expansion function is better. The performance uniformity of cold-rolled plates is better than that of pipes, and welded pipes generally use an online solid solution, which has uniform heat treatment and more stable performance. However, the mid-to low-end stainless steel welded pipes on the market now do not have heat treatment processes, so the quality varies greatly. Stainless steel seamless pipes are sampled from different directions on the same pipe, and their functions are different, and some may be quite different. During the heat treatment of seamless pipes and bundled heat pipes, there is uneven heating and inconsistent cooling rates.
(4) Appropriate in corrosion resistance. The weld has been heat-treated and now meets the material requirements. If there is no heat-treated stainless steel welded pipe, the corrosion resistance performance will be greatly reduced compared with that of stainless steel seamless pipe.
(5) The production cost of welded pipes is lower and more environmentally friendly. A good welded pipe factory can match the environment of an electronics factory; while a seamless pipe factory is full of oil and lubricants, and the pickling environment is even worse.
(6) Being under pressure is different. Under the same specification conditions, stainless steel seamless pipes can withstand higher pressure than welded pipes.
(7) The prices are different. Generally speaking, stainless steel seamless pipes are more expensive than welded pipes. But there are also the following characteristics: if it is a thick-walled pipe, it is suitable to choose seamless pipe, if it is a thin-walled pipe, it is suitable to choose welded pipe.
(8) The delivery time is different. Since stainless steel welded pipes are rolled from stainless steel plates, the processing is relatively simple, so the delivery time is shorter. Stainless steel seamless pipes start from round steel, and then go through multiple passes of cold drawn/cold rolling after perforation, and then undergo solution annealing and pickling to produce finished products. The production cycle is longer.
Post time: May-13-2024